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The inverted pendulum is a unstable non-minimum-phase plant, Hinfin output feedback control of the system is far less robust. The difficulties of control of such a plant are analysed from the viewpoint of systempsilas bandwidth: the bandwidth for control of a non-minimum-phase plant must be narrow, and the control of an unstable plant need a rather wider bandwidth. It is pointed out that a fast feedback...
GaN-based light-emitting diodes (LEDs) grown on sapphire substrates are integrated with Si by fusion bonding technique. GaN-based LEDs coated with Sn/Au are joined to Si coated with Ti/Au at 300degC in a flowing nitrogen ambient for 30 min. Sapphire substrates are separated from the samples by laser lift-off (LLO) forming GaN-based LEDs/Sn/Au/Ti/Au/Si structures. Microscopy image, observed from the...
For the difficult problem of multi-level, multi-node complicated causal network reasoning, the thesis puts forward the competition-based connectionist model resolving algorithm based on probabilistic causal network, the algorithm gives a good solution for fault diagnosis model based on the probabilistic causal network, and verifies the superiority and engineering utility for this arithmetic by solving...
This paper presents a new bit allocation strategy in JPEG2000.Every distortion value which is introduced by sub-band transmission is calculated using wavelet transform. It will obtain the ratio of every sub-bandpsilas distortion in order to determine the bits allocated to each sub-band. Simulation results show that, in the same compression rate, PSNR of the receiver reconstructed image of the proposed...
This paper introduces the disadvantages of process control experimental systems used in the colleges nowadays, designs five-vessel liquid system to replace the original three tanks and four tanks system, exploited Oxygen absorptivity measure experimental system, and designs parameter soft measure and control experiment, and found the small distributed control system to control. The control system...
In this paper the principle of millimeter-wave radiation and radioactive properties of objects are researched, we developed a single-channel direct detection of radiation-millimeter wave systems. The system uses mechanical scan mode, with the center frequency at 35 GHz, bandwidth of 4 GHz, integration time to 10 ms when the temperature resolution of 0.1 K. As the initial prototype sample, the system...
TEM horn antenna which is using as accurate measurement technology for high power ultra-wide spectrum electromagnetic pulse space radiation field is proposed. To decrease the size of measurement antenna, triangular ridged structure is used. By research and design, these two models can both realize the same radial character, get a satisfied gain and the bandwidth is enough for practical operation.
This paper addresses the problem of image compression in remote sensing applications. Compared with other still images, remote-sensing images are characterized with complex textures and weak local correlation. As a fact, RS images often contain richly directional attributes, which can be commonly approximated as linear edges on a local level. Most of current algorithms of image compression have not...
A model taking into accounts of mass conservation equation, kinetics of oxidation reaction, phase transformation has been proposed to describe the high temperature behavior of the oxidation layer of ZrB2-SiC composites along with Arrhenius law and Eshelbypsilas equivalent inclusion theorem. Volume fraction change of constituents and the elastic modulus of the depletion layer have been theoretically...
The performance of array may be seriously degraded by the difference of phase responses between the array elements. Thus it is important to compensate these differences by means of precise phase estimation. In this paper, two methods for phase difference estimation between linear array elements are presented. The first one works by applying the cost function to search the optimal source position before...
Consider the parameter uncertainty of the wind power station, wind turbine system state space model with uncertainty and disturb is modeled. State estimation Kalman filter for wind turbine system is designed based on Kalman filter theory. The effectiveness of the proposed Kalman filter is demonstrated with a simulation example.
Two results on robustness of observability for linear time-varying systems are presented, based on which, it is shown that, the observability of corresponding linearized system implies local observability of the original nonlinear system. A numerical example is given to demonstrate the presented result.
This paper proposes a new guidance law for the impact angle control, using the variable structure control theory. The guidance law has the ability to simultaneously achieve design specifications on miss distance and final missile-target relative orientation. The latter specification may be used to enhance the performance of warheads whose effectiveness is influenced by the terminal encounter geometry...
The portable testing system for UAV (The unmanned aircraft vehicle) is introduced, the design of hardwares and softwares are elaborated, the key questions in the software design are also discussed.
In order to evaluate the optimization efficiency of Genetic Algorithms (GA), this paper presents an efficiency evaluation criterion based on average optimization generation and time efficiency of GA, which not only can avoid infection evaluating the efficiency of GA on random factors commendably, but also consider the time firstly. So that it provides gist of evaluation criterion and theory for selecting...
The coordinated attack strategy that plenty of sub-munitions attack multiple targets is one of key technologies in the networked smart sub-munitions studies. The distance and the encounter angle are the two main influence factors in the sub-munitions allocation. The decision-making model of coordinated attack strategy is built. The ant colony algorithm for the coordination attack strategy of sub-munitions...
Model system based on moment theory, blade element theory and FlightLab software is designed for small-size unmanned helicopter. The system includes three models of helicopter, moment theory model (MTM), blade element theory model (BETM) and FlightLab model (FLM). MTM is used mainly for performance analysis, BETM for control system design and FLM for nonlinear real-time simulation. Then a high-reliable...
A new intra-vehicular free-flyer location and navigation methodology is introduced which adopted the state of art radio location and navigation technology called Pseudolite (PL). Theoretical analysis demonstrates the efficiency of this method. It will greatly improve intra-vehicular free-flyer navigation accuracy to satisfy future needs in deep space exploration and space structure maintenance. PL...
This paper presents a control scheme for the synchronization of chaotic systems when the same chaotic system with the different initial conditions. For a given chaotic system, an adaptive observer-based response can be constructed to synchronize the drive system. Moreover this scheme uses the nonlinear controller which is achieved the global synchronization and the proposed controller doesnpsilat...
A new method of the optimal sliding mode variable structure control is presented to eliminate the extraneous torque in the load simulator. The mathematical model of the load simulator is enlarged by incorporating the torque reference input with integral action. By proper state transformation, the construction of the optimal sliding surface equals to the design of the feedback matrix in the linear...
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